A video signal includes a large amount of information, and is difficult for storage and transmission, and therefore, video signals need to be compressed, so that the video signals are compressed. Redundancy information in a video signal includes time redundancy, space redundancy, compression redundancy, visual redundancy, and the like, and video compression aims to eliminate various types of redundancy to the maximum extent.
Currently, a major video signal compression standard is the H.264 (MPEG-4 Part 10) standard. In recent years, based on the H.264 standard, a new-generation video compression standard HEVC also appears. HEVC still follows a hybrid compression framework that is used by H.264 and includes inter-frame and intra-frame prediction compression which eliminates relevance between a time domain and a space domain; transform compression which is performed on a residue to eliminate space relevance; and entropy compression which eliminates statistical redundancy.
Currently, decoders of many terminal devices are H.264 decoders, and high efficiency video coding (HEVC) is a new standard and therefore, a video compressor needs to support both the standards. In this way, H.264 compressors will inevitably coexist with HEVC compressors within a certain time, and it is required that a compressor supports both the H.264 standard and the HEVC standard. In the prior art, a compressor implements H.264 compression and HEVC compression by using two chips respectively, leading to huge resource consumption and high costs.